Various types of compressors are known, for example reciprocating or rotary. The compressor is for example driven by an electric motor and the assembly formed by the compressor and the motor is called a moto compressor. In refrigeration machines, the compressor and the motor associated with it are usually enclosed inside a hermetic casing. The component thus produced is hereinafter called a sealed compressor. The electrical connection of the motor passes through the hermetic casing and the sealed compressor is supplied with several terminals emerging from the casing to which a power supply cable is connected during installation of the thermodynamic machine.
The cable ends in electrical connection means which are plugged onto the power supply terminals of the sealed compressor. This assembly is then covered with an electrical cover to ensure the safety of the equipment and persons using the equipment operating the thermodynamic machine. Furthermore, means for connection to earth, connected to a particular terminal passing through the casing, is used to connect the equipment to an earth connection provided by the mains power supply for the equipment.
This terminal, called the earth terminal, is connected to a specific electric conductor of the power supply cable. This specific conductor is usually insulated by means of an insulation with a particular green and yellow color. To ensure proper connection of the specific conductor to the earth terminal, use is made of a particular connection means different to the connection means for the other conductors of the power supply cable carrying electric power. For example, the power conductors end in lugs which are simply plugged onto the power supply terminals and the earth conductor ends in a lug which is screwed onto the earth terminal.
Connecting the various conductors of the cable to the terminals passing through the casing of the sealed compressor is subject to error which can lead to immediate or short term destruction of the compressor.
In addition, the time required for connection may vary depending on the accessibility of the connection terminals of the equipment.